Humpbacks that breed in Tongan water, with legal in-water swims, singing males suspended head-down in the blue, mothers parking…Humpbacks that breed in Tongan water, with legal in-water swims, singing males suspended head-down in the blue, mothers parking calves beside your boat, and heat-runs of competing males. Combine with the Vava'u anchorages, Mariner's Cave and Swallows' Cave. Tonga banned whaling in 1978 by royal decree of King Tāufa'āhau Tupou IV after generations of subsistence hunting, and the population has rebuilt strongly. Whale swim tourism has been licensed since the 1990s and is the country's biggest tourism earner. Anchorage: Vava'u is one of the world's great sheltered cruising grounds, dozens of numbered anchorages in flat water. Hazards: No site-specific hazards noted, brief normally. Altro